Big Tokyo Quake Forecast by 2016

For a country still on edge nearly a year after the giant March 11 Tohoku earthquake, Japanese scientists Monday issued a jarring forecast: Tokyo will likely face its own large temblor within the next four years.

Researchers at Tokyo University’s Earthquake Research Institute said there’s a 70% probability the long-feared “big one” will hit the southern Kanto region, which includes Tokyo’s neon-lit jungle, by 2016. It’s an ominous consequence of last year’s game-changing magnitude 9.0 earthquake, the most powerful recorded to hit Japan.

The government agency studying seismic activity has long said the odds of a mag-7-plus quake hitting Tokyo were 70% over 30 years. But Tokyo University researchers now say that the tireless bursts of quakes in the months since March 11 are a mathematical omen signaling a strong quake will occur far sooner than later. University researchers now say the odds of Tokyo or outlying suburban areas getting hit with such a powerful quake in 30 years are now 98%.

According to the researchers, a large earthquake strikes in proportion to the number of smaller shakes — measuring about magnitude-3 to 5 — that break out in the region. In other words, the more small tremors there are, the greater the probability a devastating one will hit.

Based on observations from the Japan Meteorological Agency, the Tokyo University researchers said there has been a more-than-five-fold jump in the number of earthquakes measuring magnitude 6 or below in the Tokyo area since March 11. In all, there have been 577 earthquakes registering a magnitude-5 or above in Japan from March 11 to the end of 2011, about four times the average annual amount logged between 1996-2005, according to the JMA.

“The balance has changed since March 11,” Shinichi Sakai, a research associate at the Earthquake Research Institute, told JRT. Mr. Sakai said the March 11 quake jerked the fault lines underground in a way that has changed the coastal landscape as well as the sea bed below. It also mounted pressure on nearby sea floors like those beneath Hokkaido and the Kanto region. If the rate of smaller earthquakes persist, it is likely Tokyo will see a big one strike at its doorstep in the near future.

“It’s the same as when one person in a line of people holding hands falls then those around him are likely to get pulled down too,” said Mr. Sakai. “The Kanto region is similarly being affected by the March 11 earthquake.”

Mr. Sakai said while pinpointing the exact location of where the pending temblor will take place is impossible, researchers will attempt to narrow down field of possibilities. He said they will also revise various scenarios of what would occur given the new time frame.

The latest forecast has grabbed the attention local residents, with the term “within four years” trending on Twitter since early Monday. Some users on the microblogging site tweeted that while the threat of the big one hovered in the back of their minds, the new calculation has made them more aware of the need to make emergency preparations. By the afternoon, Japan’s major dailies had published the news prominently on their websites.

The last big quake to hit Tokyo was the Great Kanto earthquake, a magnitude-7.9 jolt that struck on Sept. 1, 1923. About 105,0000 were killed in the Tokyo metropolitan area, many of which were caused by crumbling houses and fires that quickly engulfed the city. Officials say stricter building codes and new technologies developed over the years would curb significantly the toll.

I am deaf and from Singapore. I have Bad Nightmate Because I am afraid of that Tokyo Big Earthquake on 2016 but I Believe that Huge Tsumai then Mount Fuji will wake up and eruption. but I am not sure about Moun Fuji eruption. so I reading of book about " Tokyo in 1923 ".

1:39 pm February 9, 2012

Anonymous wrote:

There is one digit too much about the casualties of Kanto earthquake in 1923. It was supposed to be 105k ppl but the article said 1 million dead/missing.

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